r129 central locking problem

[roblloyd]

I have a fob key, think thats what they call it, red button flips the key out and it has a remote on it.The remote will lock the car fully and open it fully. Sometimes i cannot open the car with the remote because it will not let me, so i flip the key out and use the key in the boot to open the car.
Key will not open drivers door just turns both ways.

 

[Dec]

What year is the car?
Is the key like the below picture?

Dec

 

[roblloyd]

r129 500sl 1991, the remote is the top one in the photos.

 

[Dec]

If the button on the remote, when pressed at the drivers side locks and unlocks all the doors, boot and fuel flap then you don’t have a vacuum leak.

You have a broken lock if, the key blade, when inserted into the drivers door lock, will not lock or unlock the drivers door.

Try the test in the picture above about 20 times to see if you always get a Red and a Blue/White light every time.

Dec

 

[roblloyd]

The remote only works on the passenger door. It will NOT work on the drivers door.Also no red or green light on the drivers door BUT i do get them on the passenger side and boot.
Done the test on the remote and its all ok.
Took drivers lock off the other day, spring looked ok but the end of the lock was a bit flimsy.

 

[Dec]

Below is a similar lock, the end of the “rod” goes into a slot in the door lock, it is the end of the rod that locks and unlocks the door, if the end of the rod is broken then the door wont lock/unlock… when the key is turnd in the lock the rod also turns, if the end is broken then it wont do its job.

You could take the other good door lock off so as to make a comparison with the drivers door lock. This might help to assess what is at fault.

The rod is a bit flimsy in that it needs to pivot slightly but it should spring back to 12 o’clock position when it is turned to the left or right when locking or unlocking… it should turn a quarter turn in either direction and spring back to 12 o’clock.

Where are thease Red and Green lights located?, mirror?

Dec
Picture source… http://forums.mercedesclub.org.uk/showthread.php?t=62486

 

[roblloyd]

Looks the same as mine,will try tomorrow after puting the pump back in. Also think the key does not work in the passinger door, its the same as the drivers. Key just works in boot lock but it does lock everything.
The red/green lights are at the side of the key. The green comes on when you open and the red comes on when you close. Stay on for about 10 secs.
Will post again tomorrow.
Thanks for your time.

 

[roblloyd]

Put the pump back on and its the samething happening again. When i unlock the pump runs on for about 40 seconds, there is a leak but i cannot find it. Did the mouth test and all the yellow lines test good. the clear line does not seem as good as the yellow, like theres a bit of play. Looked to where it runs to and it goes to the softtop compartment.
The pump does not run for as long when i lock the car up. Also key does not work in both doors, just goes from side to side. Got 6 keys with the car and there all the same.
Lights work on all locks when opening/closeing.
Any ideas?

 

[Dec]

Hi Rob, how long does the pump run for when you lock the car, how many seconds from when you press the button?

Do both doors and boot and fuel flap all lock and unlock when the remote button is operated.

Dec

 

[roblloyd]

Dec
When its locked its only 3 to 4 seconds, when its unlocked 30 seconds. its totally differant when its unlocked. The remote totally locks all the car, both door & boot and fuel cap. Taking pump apart was the answer BUT no, just the same. Do not know what to do now.
rob

 

[Dec]

Did you remove the PCB, if so did you have a thing like in the attached picture with 2 wheels at arrows?

Dec

 

[roblloyd]

Yes i did see that.

 

[Dec]

You could try turning the wheel #1 two full turns towards the other wheel, #2, you need to hold the threaded part with pliers to stop it rotating while you turn the wheel, this may or may not reduce the unlocking time down from its current 30 seconds to about 2 or 3 seconds. Turning wheel 1 two full turned might be too much and one turn may be adequate, my saying 2 turns is just a guess, trial and error may be necessary.

Mark the #1 wheel with tipex/paint like the Yellow mark on the one in the picture below so that you can put it back the way it was if this doesn’t work out.

Leave wheel 2 alone as that one is to do with unlocking and sucking.

Dec

 

[roblloyd]

Dec,I will try this tomorrow. thanks, will let you know the outcome.
Rob

 

[Dec]

That Red dye on the threaded part is an adhesive to stop the wheels moving by vibration so the will feel a bit tight when you turn them.

Do, let us know how it goes, as far as I can see , you don’t have a leak, you do have 2 locks that should lock/unlock when you turn the key, but the don’t and the fact that you can only lock the car with the remote when standing at the passenger side would indicate that there is a receiver on both sides of the car, the passenger side is receiving a signal from the remote but the driver side is not… that’s just a guess, but it seems that way to me.

It’s possible that the door locks aren’t supposed to lock the whole car, just the boot lock and the remote do that job and the door locks are for emergency entry only, in case of a flat battery for example.

Dec

 

[roblloyd]

pump

Dec.
Did what you said and moved the left wheel 1/2 turn, there was not that much room about 2 1/2 turn before you got to the right wheel. So put 1/2 turn and put the pump back. IT WORKED, the pump only goes for 3 to 4 seconds its the same opening & closeing now. it must not have been conecting in the first place.
Now need to sort out why the remote only works on the passenger door only.
The must be something wrong with the drivers door & boot recievers. Do you know where they are.
thanks for your help.
rob

 

[Dec]

That’s good, that it worked, one less problem now. I’m presuming thee must be two receivers, one for each side, does it look liker there is a receiver in the door handle, any wires seen when you removed the door handle previously? Try sitting inside the car and see if you can lock/unlock it with the remote.

Other R129 owners might comment as to how many receivers you have and where the are located. If there is? a receiver in the divers door, it could be that it is working ok but whatever wire, from the receiver, that feeds the vacuum pump might be defective and that’s where the problem is.

I though turning the key in the boot lock, locked/unlocked all doors and fuel flap?

Have you got a user manual, if you haven’t, it might be worth getting one from the main dealer, I think the are around £20.

Dec

 

[roblloyd]

locking

got 2 manual with the car but have found out 1 is a older one after 1991. it does say you the car can be opened/locked centrally at the front passenger door only if key has been removed from steering lock or, if it has been reinserted after being removed, provided it has not been turned to the right.
Sort of understand it.
Receivers are at passenger door & boot. The boot one theres something wrong so will look at that next. The car locks centrally from the boot by the key so if the remote plays up i can always lock/unlock the car.
Fuel gauge is always on empty no matter how much i put in, see a post on another site showing how to get it fixed. Opened the roof and could see someone had been there before, moved a wire and now its working. Hope it stays that way.
thanks for your help
Rob

 

[Dec]

If you can locate the working receiver in the passenger door and then move it so as it is in line of sight of the remote when the remote is at the at the driver side then that would solve the problem, at least from a convenience point of view.

The inferred signal can’t go through metal but will go through glass and plastic so wherever the receiver is located it won’t be behind metal.

Dec

 

[roblloyd]

remote

Remote would not work when sitting in the car, make sence now.the receiver is in the door handal i'm sure because thats were the lights are. Does anyone know how to get to them? Also people keep going on about sticky's, What is a sticky and were do you find them on the site?
rob